KONG™'s exclusive, nontoxic red natural rubber is puncture resistant, super bouncy and chewer friendly. It is unmatched for legendary strength, resilience, durability and bounce. KONG™ toys are enthusiastically used and recommended by veterinarians, trainers, dog professionals and satisfied customers world wide. Large KONG™s are for Borders Collies, Boxers, Dachshounds and Similar sized Mixed Breeds